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Honetschlägerová Z, Husková Z, Kikerlová S, Sadowski J, Kompanowska-Jezierska E, Táborský M, Vaňourková Z, Kujal P, Červenka L. Renal sympathetic denervation improves pressure-natriuresis relationship in cardiorenal syndrome: insight from studies with Ren-2 transgenic hypertensive rats with volume overload induced using aorto-caval fistula. Hypertens Res 2024; 47:998-1016. [PMID: 38302775 PMCID: PMC10994851 DOI: 10.1038/s41440-024-01583-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2023] [Revised: 12/20/2023] [Accepted: 12/24/2023] [Indexed: 02/03/2024]
Abstract
The aim was to evaluate the effects of renal denervation (RDN) on autoregulation of renal hemodynamics and the pressure-natriuresis relationship in Ren-2 transgenic rats (TGR) with aorto-caval fistula (ACF)-induced heart failure (HF). RDN was performed one week after creation of ACF or sham-operation. Animals were prepared for evaluation of autoregulatory capacity of renal blood flow (RBF) and glomerular filtration rate (GFR), and of the pressure-natriuresis characteristics after stepwise changes in renal arterial pressure (RAP) induced by aortic clamping. Their basal values of blood pressure and renal function were significantly lower than with innervated sham-operated TGR (p < 0.05 in all cases): mean arterial pressure (MAP) (115 ± 2 vs. 160 ± 3 mmHg), RBF (6.91 ± 0.33 vs. 10.87 ± 0.38 ml.min-1.g-1), urine flow (UF) (11.3 ± 1.79 vs. 43.17 ± 3.24 µl.min-1.g-1) and absolute sodium excretion (UNaV) (1.08 ± 0.27 vs, 6.38 ± 0.76 µmol.min-1.g-1). After denervation ACF TGR showed improved autoregulation of RBF: at lowest RAP level (80 mmHg) the value was higher than in innervated ACF TGR (6.92 ± 0.26 vs. 4.54 ± 0.22 ml.min-1.g-1, p < 0.05). Also, the pressure-natriuresis relationship was markedly improved after RDN: at the RAP of 80 mmHg UF equaled 4.31 ± 0.99 vs. 0.26 ± 0.09 µl.min-1.g-1 recorded in innervated ACF TGR, UNaV was 0.31 ± 0.05 vs. 0.04 ± 0.01 µmol min-1.g-1 (p < 0.05 in all cases). In conclusion, in our model of hypertensive rat with ACF-induced HF, RDN improved autoregulatory capacity of RBF and the pressure-natriuresis relationship when measured at the stage of HF decompensation.
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Affiliation(s)
- Zuzana Honetschlägerová
- Center for Experimental Medicine, Institute for Clinical and Experimental Medicine, Prague, Czech Republic
| | - Zuzana Husková
- Center for Experimental Medicine, Institute for Clinical and Experimental Medicine, Prague, Czech Republic
| | - Soňa Kikerlová
- Center for Experimental Medicine, Institute for Clinical and Experimental Medicine, Prague, Czech Republic
| | - Janusz Sadowski
- Department of Renal and Body Fluid Physiology, Mossakowski Medical Research Institute, Polish Academy of Sciences, Warsaw, Poland
| | - Elzbieta Kompanowska-Jezierska
- Department of Renal and Body Fluid Physiology, Mossakowski Medical Research Institute, Polish Academy of Sciences, Warsaw, Poland
| | - Miloš Táborský
- Department of Internal Medicine I, Cardiology, University Hospital Olomouc and Palacký University, Olomouc, Czech Republic
| | - Zdenka Vaňourková
- Center for Experimental Medicine, Institute for Clinical and Experimental Medicine, Prague, Czech Republic
| | - Petr Kujal
- Department of Pathology, 3rd Faculty of Medicine, Charles University, Prague, Czech Republic
| | - Luděk Červenka
- Center for Experimental Medicine, Institute for Clinical and Experimental Medicine, Prague, Czech Republic.
- Department of Internal Medicine I, Cardiology, University Hospital Olomouc and Palacký University, Olomouc, Czech Republic.
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Paukner K, Filipejova Z, Mareš J, Vávra M, Rehakova K, Proks P, Gabriel V, Crha M. A comprehensive analysis of albuminuria in canine chronic kidney disease. Vet Med Sci 2024; 10:e1403. [PMID: 38419297 PMCID: PMC10902581 DOI: 10.1002/vms3.1403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Revised: 01/29/2024] [Accepted: 02/09/2024] [Indexed: 03/02/2024] Open
Abstract
BACKGROUND Albuminuria, an important marker of decreased kidney function in chronic kidney disease (CKD), is not routinely used for CKD detection or proteinuria appearance. Its relationships with biochemical parameters and blood pressure in dogs are poorly understood. OBJECTIVES This study aimed to evaluate the relationship of albuminuria with various CKD markers, its correlation with the urinary protein to creatinine ratio (UPC), and hypertension in dogs with early stages of CKD. It also sought to determine the usability of the urinary albumin to creatinine ratio (UAC) for CKD screening. METHODS The study reviewed records of 102 dogs, categorising them into four groups based on disease status. UAC and UPC ratio, biochemistry and haematology variables, age, and systolic blood pressure were determined. RESULTS The Pearson's correlation coefficient between log-transformed values of UPC and UAC was r = 0.902 (95% CI: 0.87 to 0.93). Median UAC ratio values were 2.1 mg/g for the Healthy control group (n = 17), 54.2 mg/g for early stages CKD (n = 42), 5.8 mg/g for Acute sick control (n = 30), and 104 mg/g for Chronic sick control (n = 13). Thresholding UAC ratio as an indicator for impaired kidney function with the threshold of 10 mg/g (established based on the receiver operating characteristic curve) had a sensitivity 81.8%, specificity of 89.4%, positive predictive value (PPV) 90%, and negative predictive value (NPV) 80.1%. The correlation of UAC with biochemistry and haematology variables was statistically significant; for SDMA (μg/L), it was r = 0.566 and for other variables, it was weak to moderate. UAC was markedly elevated in cases of severe hypertension. CONCLUSIONS UAC ratio was significantly different among dogs with impaired and not impaired kidney function. The correlation strength for the UAC and UPC ratios was high. UAC ratio may be a promising marker for proteinuria analysis in dogs with CKD or other kidney function alterations.
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Affiliation(s)
- Karel Paukner
- Small Animal ClinicUniversity of Veterinary Sciences BrnoBrnoCzech Republic
- Center for Experimental MedicineInstitute for Clinical and Experimental MedicinePragueCzech Republic
| | - Zita Filipejova
- Small Animal ClinicUniversity of Veterinary Sciences BrnoBrnoCzech Republic
| | - Jan Mareš
- Department of Data ScienceInstitute for Clinical and Experimental MedicinePragueCzech Republic
| | - Miloš Vávra
- Small Animal ClinicUniversity of Veterinary Sciences BrnoBrnoCzech Republic
| | - Kristina Rehakova
- Small Animal Clinical LaboratoryUniversity of Veterinary Sciences BrnoBrnoCzech Republic
| | - Pavel Proks
- Small Animal ClinicUniversity of Veterinary Sciences BrnoBrnoCzech Republic
| | - Vojtech Gabriel
- Department of Biomedical SciencesCollege of Veterinary Medicine, Iowa State UniversityAmesIowaUSA
| | - Michal Crha
- Small Animal ClinicUniversity of Veterinary Sciences BrnoBrnoCzech Republic
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Gawrys O, Husková Z, Škaroupková P, Honetschlägerová Z, Vaňourková Z, Kikerlová S, Melenovský V, Bačová BS, Sykora M, Táborský M, Červenka L. The treatment with sGC stimulator improves survival of hypertensive rats in response to volume-overload induced by aorto-caval fistula. NAUNYN-SCHMIEDEBERG'S ARCHIVES OF PHARMACOLOGY 2023; 396:3757-3773. [PMID: 37338578 PMCID: PMC10643302 DOI: 10.1007/s00210-023-02561-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Accepted: 05/30/2023] [Indexed: 06/21/2023]
Abstract
Heart failure (HF) has been declared as global pandemic and current therapies are still ineffective, especially in patients that develop concurrent cardio-renal syndrome. Considerable attention has been focused on the nitric oxide (NO)/soluble guanylyl cyclase (sGC)/cyclic guanosine monophosphate (cGMP) pathway. In the current study, we aimed to investigate the effectiveness of sGC stimulator (BAY41-8543) with the same mode of action as vericiguat, for the treatment of heart failure (HF) with cardio-renal syndrome. As a model, we chose heterozygous Ren-2 transgenic rats (TGR), with high-output heart failure, induced by aorto-caval fistula (ACF). The rats were subjected into three experimental protocols to evaluate short-term effects of the treatment, impact on blood pressure, and finally the long-term survival lasting 210 days. As control groups, we used hypertensive sham TGR and normotensive sham HanSD rats. We have shown that the sGC stimulator effectively increased the survival of rats with HF in comparison to untreated animals. After 60 days of sGC stimulator treatment, the survival was still 50% compared to 8% in the untreated rats. One-week treatment with sGC stimulator increased the excretion of cGMP in ACF TGR (109 ± 28 nnmol/12 h), but the ACE inhibitor decreased it (-63 ± 21 nnmol/12 h). Moreover, sGC stimulator caused a decrease in SBP, but this effect was only temporary (day 0: 117 ± 3; day 2: 108 ± 1; day 14: 124 ± 2 mmHg). These results support the concept that sGC stimulators might represent a valuable class of drugs to battle heart failure especially with cardio-renal syndrome, but further studies are necessary.
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Affiliation(s)
- Olga Gawrys
- Experimental Medicine Centre, Institute for Clinical and Experimental Medicine, Prague, Czech Republic.
| | - Zuzana Husková
- Experimental Medicine Centre, Institute for Clinical and Experimental Medicine, Prague, Czech Republic
| | - Petra Škaroupková
- Experimental Medicine Centre, Institute for Clinical and Experimental Medicine, Prague, Czech Republic
| | - Zuzana Honetschlägerová
- Experimental Medicine Centre, Institute for Clinical and Experimental Medicine, Prague, Czech Republic
| | - Zdeňka Vaňourková
- Experimental Medicine Centre, Institute for Clinical and Experimental Medicine, Prague, Czech Republic
| | - Soňa Kikerlová
- Experimental Medicine Centre, Institute for Clinical and Experimental Medicine, Prague, Czech Republic
| | - Vojtěch Melenovský
- Department of Cardiology, Institute for Clinical and Experimental Medicine, Prague, Czech Republic
| | - Barbara Szeiffová Bačová
- Centre of Experimental Medicine, Slovak Academy of Sciences, Institute for Heart Research, Bratislava, Slovakia
| | - Matúš Sykora
- Centre of Experimental Medicine, Slovak Academy of Sciences, Institute for Heart Research, Bratislava, Slovakia
| | - Miloš Táborský
- Department of Internal Medicine I, Cardiology, University Hospital Olomouc and Palacký University, Olomouc, Czech Republic
| | - Luděk Červenka
- Experimental Medicine Centre, Institute for Clinical and Experimental Medicine, Prague, Czech Republic
- Department of Internal Medicine I, Cardiology, University Hospital Olomouc and Palacký University, Olomouc, Czech Republic
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Honetschlägerová Z, Sadowski J, Kompanowska-Jezierska E, Maxová H, Táborský M, Kujal P, Červenka L. Impaired renal autoregulation and pressure-natriuresis: any role in the development of heart failure in normotensive and angiotensin II-dependent hypertensive rats? Hypertens Res 2023; 46:2340-2355. [PMID: 37592042 PMCID: PMC10550820 DOI: 10.1038/s41440-023-01401-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Revised: 06/30/2023] [Accepted: 07/28/2023] [Indexed: 08/19/2023]
Abstract
The aim of the present study was to assess the autoregulatory capacity of renal blood flow (RBF) and of the pressure-natriuresis characteristics in the early phase of heart failure (HF) in rats, normotensive and with angiotensin II (ANG II)-dependent hypertension. Ren-2 transgenic rats (TGR) were employed as a model of ANG II-dependent hypertension. HF was induced by creating the aorto-caval fistula (ACF). One week after ACF creation or sham-operation, the animals were prepared for studies evaluating in vivo RBF autoregulatory capacity and the pressure-natriuresis characteristics after stepwise changes in renal arterial pressure (RAP) induced by aortic clamping. In ACF TGR the basal mean arterial pressure, RBF, urine flow (UF), and absolute sodium excretion (UNaV) were all significantly lower tha n in sham-operated TGR. In the latter, reductions in renal arterial pressure (RAP) significantly decreased RBF whereas in ACF TGR they did not change. Stepwise reductions in RAP resulted in marked decreases in UF and UNaV in sham-operated as well as in ACF TGR, however, these decreases were significantly greater in the former. Our data show that compared with sham-operated TGR, ACF TGR displayed well-maintained RBF autoregulatory capacity and improved slope of the pressure-natriuresis relationship. Thus, even though in the very early HF stage renal dysfunction was demonstrable, in the HF model of ANG II-dependent hypertensive rat such dysfunction and the subsequent HF decompensation cannot be simply ascribed to impaired renal autoregulation and pressure-natriuresis relationship.
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Affiliation(s)
- Zuzana Honetschlägerová
- Center for Experimental Medicine, Institute for Clinical and Experimental Medicine, Prague, Czech Republic.
| | - Janusz Sadowski
- Department of Renal and Body Fluid Physiology, Mossakowski Medical Research Institute, Polish Academy of Sciences, Warsaw, Poland
| | - Elzbieta Kompanowska-Jezierska
- Department of Renal and Body Fluid Physiology, Mossakowski Medical Research Institute, Polish Academy of Sciences, Warsaw, Poland
| | - Hana Maxová
- Department of Pathophysiology, 2nd Faculty of Medicine, Charles University, Prague, Czech Republic
| | - Miloš Táborský
- Department of Internal Medicine I, Cardiology, University Hospital Olomouc and Palacký University, Olomouc, Czech Republic
| | - Petr Kujal
- Department of Pathology, 3rd Faculty of Medicine, Charles University, Prague, Czech Republic
| | - Luděk Červenka
- Center for Experimental Medicine, Institute for Clinical and Experimental Medicine, Prague, Czech Republic
- Department of Internal Medicine I, Cardiology, University Hospital Olomouc and Palacký University, Olomouc, Czech Republic
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Kala P, Vaňourková Z, Škaroupková P, Kompanowska-Jezierska E, Sadowski J, Walkowska A, Veselka J, Táborský M, Maxová H, Vaněčková I, Červenka L. Endothelin type A receptor blockade increases renoprotection in congestive heart failure combined with chronic kidney disease: Studies in 5/6 nephrectomized rats with aorto-caval fistula. Biomed Pharmacother 2023; 158:114157. [PMID: 36580726 DOI: 10.1016/j.biopha.2022.114157] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Revised: 12/11/2022] [Accepted: 12/21/2022] [Indexed: 12/28/2022] Open
Abstract
BACKGROUND Association of congestive heart failure (CHF) and chronic kidney disease (CKD) worsens the patient's prognosis and results in poor survival rate. The aim of this study was to examine if addition of endothelin type A (ETA) receptor antagonist to the angiotensin-converting enzyme inhibitor (ACEi) will bring additional beneficial effects in experimental rats. METHODS CKD was induced by 5/6 renal mass reduction (5/6 NX) and CHF was elicited by volume overload achieved by creation of aorto-caval fistula (ACF). The follow-up was 24 weeks after the first intervention (5/6 NX). The treatment regimens were initiated 6 weeks after 5/6 NX and 2 weeks after ACF creation. RESULTS The final survival in untreated group was 15%. The treatment with ETA receptor antagonist alone or ACEi alone and the combined treatment improved the survival rate to 64%, 71% and 75%, respectively, however, the difference between the combination and either single treatment regimen was not significant. The combined treatment exerted best renoprotection, causing additional reduction in albuminuria and reducing renal glomerular and tubulointerstitial injury as compared with ACE inhibition alone. CONCLUSIONS Our results show that treatment with ETA receptor antagonist attenuates the CKD- and CHF-related mortality, and addition of ETA receptor antagonist to the standard blockade of RAS by ACEi exhibits additional renoprotective actions.
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Affiliation(s)
- Petr Kala
- Department of Cardiology, University Hospital Motol and 2nd Faculty of Medicine, Charles University, Prague, Czech Republic; Center for Experimental Medicine, Institute for Clinical and Experimental Medicine, Prague, Czech Republic.
| | - Zdenka Vaňourková
- Center for Experimental Medicine, Institute for Clinical and Experimental Medicine, Prague, Czech Republic
| | - Petra Škaroupková
- Center for Experimental Medicine, Institute for Clinical and Experimental Medicine, Prague, Czech Republic
| | - Elżbieta Kompanowska-Jezierska
- Department of Renal and Body Fluid Physiology, Mossakowski Medical Research Institute, Polish Academy of Science, Warsaw, Poland
| | - Janusz Sadowski
- Department of Renal and Body Fluid Physiology, Mossakowski Medical Research Institute, Polish Academy of Science, Warsaw, Poland
| | - Agnieszka Walkowska
- Department of Renal and Body Fluid Physiology, Mossakowski Medical Research Institute, Polish Academy of Science, Warsaw, Poland
| | - Josef Veselka
- Department of Cardiology, University Hospital Motol and 2nd Faculty of Medicine, Charles University, Prague, Czech Republic
| | - Miloš Táborský
- Department of Internal Medicine I, Cardiology, University Hospital Olomouc and Palacký University, Olomouc, Czech Republic
| | - Hana Maxová
- Department of Pathophysiology, 2nd Faculty of Medicine, Charles University, Prague, Czech Republic
| | - Ivana Vaněčková
- Institute of Physiology, Czech Academy of Sciences, Czech Republic
| | - Luděk Červenka
- Center for Experimental Medicine, Institute for Clinical and Experimental Medicine, Prague, Czech Republic; Department of Internal Medicine I, Cardiology, University Hospital Olomouc and Palacký University, Olomouc, Czech Republic
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Kala P, Gawrys O, Miklovič M, Vaňourková Z, Škaroupková P, Jíchová Š, Sadowski J, Kompanowska-Jezierska E, Walkowska A, Veselka J, Táborský M, Maxová H, Vaněčková I, Červenka L. Endothelin type A receptor blockade attenuates aorto-caval fistula-induced heart failure in rats with angiotensin II-dependent hypertension. J Hypertens 2023; 41:99-114. [PMID: 36204993 PMCID: PMC9794157 DOI: 10.1097/hjh.0000000000003307] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2022] [Revised: 08/06/2022] [Accepted: 09/07/2022] [Indexed: 02/01/2023]
Abstract
OBJECTIVE Evaluation of the effect of endothelin type A (ET A ) receptor blockade on the course of volume-overload heart failure in rats with angiotensin II-dependent hypertension. METHODS Ren-2 renin transgenic rats (TGR) were used as a model of hypertension. Heart failure was induced by creating an aorto-caval fistula (ACF). Selective ET A receptor blockade was achieved by atrasentan. For comparison, other rat groups received trandolapril, an angiotensin-converting enzyme inhibitor (ACEi). Animals first underwent ACF creation and 2 weeks later the treatment with atrasentan or trandolapril, alone or combined, was applied; the follow-up period was 20 weeks. RESULTS Eighteen days after creating ACF, untreated TGR began to die, and none was alive by day 79. Both atrasentan and trandolapril treatment improved the survival rate, ultimately to 56% (18 of 31 animals) and 69% (22 of 32 animals), respectively. Combined ACEi and ET A receptor blockade improved the final survival rate to 52% (17 of 33 animals). The effects of the three treatment regimens on the survival rate did not significantly differ. All three treatment regimens suppressed the development of cardiac hypertrophy and lung congestion, decreased left ventricle (LV) end-diastolic volume and LV end-diastolic pressure, and improved LV systolic contractility in ACF TGR as compared with their untreated counterparts. CONCLUSION The treatment with ET A receptor antagonist delays the onset of decompensation of volume-overload heart failure and improves the survival rate in hypertensive TGR with ACF-induced heart failure. However, the addition of ET A receptor blockade did not enhance the beneficial effects beyond those obtained with standard treatment with ACEi alone.
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Affiliation(s)
- Petr Kala
- Center for Experimental Medicine, Institute for Clinical and Experimental Medicine
- Department of Cardiology, University Hospital Motol and 2nd Faculty of Medicine, Charles University, Prague, Czech Republic
| | - Olga Gawrys
- Center for Experimental Medicine, Institute for Clinical and Experimental Medicine
- Department of Renal and Body Fluid Physiology, Mossakowski Medical Research Institute, Polish Academy of Science, Warsaw, Poland
| | - Matúš Miklovič
- Center for Experimental Medicine, Institute for Clinical and Experimental Medicine
| | - Zdenka Vaňourková
- Center for Experimental Medicine, Institute for Clinical and Experimental Medicine
| | - Petra Škaroupková
- Center for Experimental Medicine, Institute for Clinical and Experimental Medicine
| | - Šárka Jíchová
- Center for Experimental Medicine, Institute for Clinical and Experimental Medicine
| | - Janusz Sadowski
- Department of Renal and Body Fluid Physiology, Mossakowski Medical Research Institute, Polish Academy of Science, Warsaw, Poland
| | - Elzbieta Kompanowska-Jezierska
- Department of Renal and Body Fluid Physiology, Mossakowski Medical Research Institute, Polish Academy of Science, Warsaw, Poland
| | - Agnieszka Walkowska
- Department of Renal and Body Fluid Physiology, Mossakowski Medical Research Institute, Polish Academy of Science, Warsaw, Poland
| | - Josef Veselka
- Department of Cardiology, University Hospital Motol and 2nd Faculty of Medicine, Charles University, Prague, Czech Republic
| | - Miloš Táborský
- Department of Internal Medicine I, Cardiology, University Hospital Olomouc and Palacký University, Olomouc
| | - Hana Maxová
- Department of Pathophysiology, 2nd Faculty of Medicine, Charles University
| | - Ivana Vaněčková
- Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic
| | - Luděk Červenka
- Center for Experimental Medicine, Institute for Clinical and Experimental Medicine
- Department of Internal Medicine I, Cardiology, University Hospital Olomouc and Palacký University, Olomouc
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Effects of Renal Denervation on the Enhanced Renal Vascular Responsiveness to Angiotensin II in High-Output Heart Failure: Angiotensin II Receptor Binding Assessment and Functional Studies in Ren-2 Transgenic Hypertensive Rats. Biomedicines 2021; 9:biomedicines9121803. [PMID: 34944619 PMCID: PMC8698780 DOI: 10.3390/biomedicines9121803] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Revised: 11/16/2021] [Accepted: 11/27/2021] [Indexed: 02/01/2023] Open
Abstract
Detailed mechanism(s) of the beneficial effects of renal denervation (RDN) on the course of heart failure (HF) remain unclear. The study aimed to evaluate renal vascular responsiveness to angiotensin II (ANG II) and to characterize ANG II type 1 (AT1) and type 2 (AT2) receptors in the kidney of Ren-2 transgenic rats (TGR), a model of ANG II-dependent hypertension. HF was induced by volume overload using aorto-caval fistula (ACF). The studies were performed two weeks after RDN (three weeks after the creation of ACF), i.e., when non-denervated ACF TGR enter the decompensation phase of HF whereas those after RDN are still in the compensation phase. We found that ACF TGR showed lower renal blood flow (RBF) and its exaggerated response to intrarenal ANG II (8 ng); RDN further augmented this responsiveness. We found that all ANG II receptors in the kidney cortex were of the AT1 subtype. ANG II receptor binding characteristics in the renal cortex did not significantly differ between experimental groups, hence AT1 alterations are not responsible for renal vascular hyperresponsiveness to ANG II in ACF TGR, denervated or not. In conclusion, maintained renal AT1 receptor binding combined with elevated ANG II levels and renal vascular hyperresponsiveness to ANG II in ACF TGR influence renal hemodynamics and tubular reabsorption and lead to renal dysfunction in the high-output HF model. Since RDN did not attenuate the RBF decrease and enhanced renal vascular responsiveness to ANG II, the beneficial actions of RDN on HF-related mortality are probably not dominantly mediated by renal mechanism(s).
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Effects of Epoxyeicosatrienoic Acid-Enhancing Therapy on the Course of Congestive Heart Failure in Angiotensin II-Dependent Rat Hypertension: From mRNA Analysis towards Functional In Vivo Evaluation. Biomedicines 2021; 9:biomedicines9081053. [PMID: 34440257 PMCID: PMC8393645 DOI: 10.3390/biomedicines9081053] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Revised: 08/16/2021] [Accepted: 08/18/2021] [Indexed: 12/27/2022] Open
Abstract
This study evaluates the effects of chronic treatment with EET-A, an orally active epoxyeicosatrienoic acid (EETs) analog, on the course of aorto-caval fistula (ACF)-induced heart failure (HF) in Ren-2 transgenic rats (TGR), a model characterized by hypertension and augmented activity of the renin-angiotensin system (RAS). The results were compared with standard pharmacological blockade of the RAS using angiotensin-converting enzyme inhibitor (ACEi). The rationale for employing EET-A as a new treatment approach is based on our findings that apart from increased RAS activity, untreated ACF TGR also shows kidney and left ventricle (LV) tissue deficiency of EETs. Untreated ACF TGR began to die 17 days after creating ACF and were all dead by day 84. The treatment with EET-A alone or ACEi alone improved the survival rate: in 156 days after ACF creation, it was 45.5% and 59.4%, respectively. The combined treatment with EET-A and ACEi appeared to improve the final survival to 71%; however, the difference from either single treatment regimen did not reach significance. Nevertheless, our findings support the notion that targeting the cytochrome P-450-dependent epoxygenase pathway of arachidonic acid metabolism should be considered for the treatment of HF.
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